DESCRIPTION: (Applicant's Abstract) This proposal for a K24 Mid-Career Investigator Award is being submitted to the National Institute on Drug Abuse (NIDA) for the support of Dr. Richard D. Moore to continue and enhance a program of patient-oriented research and training focused on HIV-infected patients with a history of drug abuse. Supported by a prior 5-year R01 from AHCPR and now an RO1 from NIDA, Dr. Moore has developed a longitudinal database of HIV-infected patients receiving care in an urban HIV center. This database captures comprehensive information on the treatment and subsequent clinical progression of HIV infection. The methodology is well-established and the database currently has over 10,000 person-years of follow-up time. The patients are predominantly of minority race and poor, with a high proportion of women. Illicit drug use is the most common risk factor for HIV transmission (>50 percent of all new enrollees) with active illicit drug use a continuing problem in the majority of these patients. The current focus of Dr. Moore's research efforts is on the HIV-infected illicit drug user. The specific research aims of this proposal are: 1 ) assess utilization patterns of new antiretroviral and other drug therapy, 2) assess the long-term effectiveness of combination antiretroviral therapy in slowing progression of HIV disease and prolonging survival, and 3) assess the costs of HIV care. Preliminary data suggest that illicit drug users may be less likely to receive or maintain use of HIV therapy and have a higher rate of failure with poorer outcomes than non-drug users. Determining the reasons for this and designing interventions to improve outcomes is critical future goal in order to save lives and reduce transmission of resistant HIV. Dr. Moore's research and training program have been highly productive with over 125 manuscripts and abstracts produced and over 25 postdoctoral fellows, graduate students and other young investigators mentored. This K24 Award will be an important contribution to future research productivity at the interface of HIV infection and substance abuse, and in the mentoring and training of future clinical investigators.